Calculate the L4 approximation for f(x) = cos² x on n [777]. (Round your answer to four decimal places.) L4 = 10.3790 3 Divide the given interval into four subintervals of equal width Ax. Let xo, X1, X2, and x3 be the left endpoints of the subintervals. What are the numerical values of Ax and xo, X1, X2, X3? Recall that L4 = f(x)Ax. k=0 Additional Materials Tutorial